Die loading apparatus for power presses



March 5, 1968 E. A. MUNSCHAUER, JR 3,

DIE LOADING APPARATUS FOR POWER PRESSES Filed Feb. 7, 1966 5Sheets-Sheet 1 INVENTOR. EDWIN A. MUNSCH/IUER, JR.

ATTORNEYS March 5, 1968 E. A. MUNSCHAUER,JR. 3,371,515

DIE-LOADING APPARATUS FOR POWER PRESSES Filed Feb 7, 1966 f I sSheets-Sheet 2 INVENTOR. EDW/N 17. MU/VJCHHUEP, JR.

' ATTORNEYS March 5, 1968' E. A. MUNSCHAUER,JR. 3,

DIE LOADING APPARATUS FOR POWER PRESSES Filed Feb. 7, 1966 v 3Sheets-Sheet 5 INVENTOR. EDW/N 4. MUNSCH IUEQ. JR.

BY M4/3W UnitedStates Patent 3,371,515 DIE LOADING APPARATUS FOR POWERPRESSES Edwin A. Munschauer, Jr., Snyder, N.Y., assignor to NiagaraMachine & Tool Works, Buffalo, N.Y. Filed Feb. 7, 1966, Ser. No. 525,56010 Claims. (Cl. 72-446) This invention relates to apparatus for changingdies in conventional power presses, that is, for moving a die intoworking position on the bed of a press and for removing such die whenanother die is to be introduced.

Dies such as are used in power presses for performing metal stampingoperations are frequently of such size and weight that bringing them toworking position on the bed of a power press presents a substantialproblem. Traveling cranes such as are used in power press rooms canbring the die to a point adjacent to the press but the superstructure ofthe press prevents depositing the die directly on the press bed by thecrane.

Apparatus for moving die mechanisms from a point adjacent to a powerpress to the operating position on the press bed have been proposed, asin United States Patents No. 3,183,828 dated May 18, 1965, and No.3,207,065 dated Sept. 21, 1965. These patents provide carriages uponwhich a die may be placed with the carriage adjacent to the press,whereupon the carriage is moved into the press over the bed thereof tobring the die into position beneath the ram or slide of the press.

In these prior art devices the supporting wheel upon which the carriagesmove are supported on eccentric axles or shafts and the eccentricity ofthe axles or shafts must be adjusted to lower a die onto the press bedor raise it therefrom. This eccentric adjustment of the wheel supportingshafts is costly to manufacture and complicated in operation,particularly since the carriages are preferably power driven and both ofthe aforesaid prior patents require eccentric adjustment of the powerdriven wheels of the carriages.

The apparatus of the present invention provides a carriage mechanismwherein the lowering and raising movements necessary to effect placementof a die on the press bed or removal therefrom are accomplished by asimple expedient involving no adjustment of the wheel axes with respectto the carriage supported thereby.

Further objects of the die loading apparatus of the present inventionconsist in providing die loading means which is readily adaptable topower presses of various types and sizes and means involving simplecontrols for successively moving a die set into a press then lowering tothe press bed, or vice versa.

While several specific embodiments of the principles of the presentinvention are illustrated in the accompanying drawing and described indetail in the following specification, it is to be understood that suchembodiments are by way of example only and that various mechanicalmodifications may be made without departing from the spirit of theinvention, the scope of which is limited only as defined in the appendedclaims.

In the drawings:

.FIG. 1 is a' perspective view of one form of conventional power presswith a die loading apparatus constructed according to one form of thepresent invention associate-d therewith and shown in its inner positionwith respect to the press;

FIG. 2 is a fragmentary cross sectional view taken on a fore and aftvertical plane through the bed portion of the power press of FIG. 1 andthrough the associated die loading apparatus;

FIG. 3 is a view similar to FIG. 2, but with the parts in a finalposition in'the die loading cycle;

FIG. 4 is a view similar to FIG. 3 showing the die loading apparatus ofthe present invention modified to accommodate a die set and power presswhich employs a conventional pressure pad;

1 FIG. is a fragmentary cross sectional view taken on 5 a vertical planeextending from side to side of the bed portionv of a power press showingapparatus for alternatively employing either of a pair of die sets.

Like characters of reference denote like parts throughout the severalfigures of the drawings and, in the embodiment of FIGS. 1 through 3, andreferring particularly to FIG. 1, a conventional power press is shownhaving a bed 10, four corner columns 11, and a crown 12. The die loadingapparatus of the present invention is designated generally in FIG. 1 bythe numeral 14 and in the form illustrated comprises a bolster 15 uponwhich a die set is mounted and secured in the usual manner. In FIGS. 2and 3 the die set is designated 16.

A generally vertical plate 17 is secured along its upper edge to thefront edge of bolster 15 by means of a retaining bar 18. Plate 17 servesas a frame member for a front carriage support for bolster 15, whichcarriage includes a bottom plate 19 which is fixed to the lower portionof plate 17.

The front carriage support rides on a pair of tracks 20 by way of'wheels 21 mounted on a shaft 22 which is journaled in bearing brackets23 fixed to the underside of bottom plate 19. An electric motor 24 and areducer unit 25 are mounted against plate 17 and the output shaft ofreducer 25 drives wheel shaft 22 by way of a chain and sprocket or beltand pulley connection as at 26 in FIG. 2. As shown at 27 in FIG. 1,motor 24 may be connected to the general control panel of the powerpress. An enclosure for the foregoing wheel drive mechanism is shown at28 in FIGS. 2 and 3.

A pair of wheels 30 are carried for free rotation by brackets 31 fixedto the rear face of bolster 15. The lower peripheries of rear wheels 30project below the lower face of bolster 15. In the forward position ofthe foregoing 1 die loading apparatus the bolster 15 extends out to theright of bed 10 as viewed in FIGS. 2 and 3, that is, forwardly of thepower press, with the Wheels 30 resting on the front upper surface ofbed 10. In this position the upper surface of bolster 15 is freelyaccessible from above so that a die set may be deposited thereon orremoved therefrom by a traveling crane or other hoisting or liftingapparatus.

When a die set has thus been deposited on bed 10 the motor 24 isactivated and the bolster 15 and the front carriage thereof moves to theleft as viewed in FIGS. 2 and 3, the wheels 30 rolling freely on bed 10.If desired guiding grooves or tracks may be provided on bed 10 forwheels 30. After wheels 30 thus traverse bed 10 from front to rear thewheels 30 move onto supports 32 which comprise plate members fixed tothe upper end of rods 33 which connect with pistons (not shown) of fluidpressure cylinders 34.

Various means may be employed for selectively energizing the fluidpressure cylinders 34 to raise the support plates 32 to the full lineposition illustrated in FIG. 2 or lower them to the position illustratedin FIG. 3 By way of example, conduits 35 from cylinders 34 may lead to ahand pump 36 of a type known and employed in this art for operatinghydraulic jacks which are employed in raising die sets on power pressbeds in order to permit fork lifts to engage beneath the die sets. Othersources of fluid pressure with appropriate control valves may beemployed.

In their upper positions the support plates 32 form rearwardcontinuations of the upper surface of bed 10 so that upon movement ofthe carriage toward the press to bring the bolster into working positionon the press bed the wheels 30 move across the bed and onto the supportplates 32 as shown in FIG. 2. It will be noted that the under surface ofbolster 15 is at an angle to the top of bed when the parts are inposition shown in FIG. 2. This angle is such that, when the bolster andcarriage apparatus is pivoted on wheels 21 in a counterclockwisedirection from the position illustrated in FIG. 2 the bottom of bolstercomes down flat against the upper surface of bed 10. Ideally, the lowersurface of bolster 15 is tangent to an arc struck from the axis of wheelshaft 22 and of a radius equal to the vertical distance from such axisto the surface of bed 10.

One or more locating pins 38 carried by bolster 15 are adapted to enterholes 39 in bed 10 when the bolster is in working position. The locatingpins may be spring backed so as to yield upwardly until they come intoregistry with holes 39, such construction being well known in this art.

The embodiment illustrated in FIG. 4 is the same as the primaryembodiment excepting that the bolster element is modified to cooperatewith a power press equipped with an air cushion, such cushions beingcommonly employed when metal drawing dies are used in a power press. InFIG. 4 a press bed 40 is supported by columns or legs 41 and has acentral opening for receiving a pressure pad 42 at the upper end of acylinder 43 which fits over'a stationary piston 44, the pad being urgedupwardly by the application of compressed air to the interior ofcylinder 43 beneath pressure pad 42.

FIG. 4 shows, somewhat schematically, a conventional draw die apparatuscomprising a die holder 45 secured to a bolster designated generally 46and a punch holder 47 which is attached to the slide of the press forvertical reciprocation in a conventional manner. A male die 48 is fixedto die holder 45 and a complementary female die 49 is fixed to punchholder 47. In the present instance the die set is a combination blankingand draw die and a blanking die ring 51 is fixed to the die holder, thefemale die 49 comprising the complementary blanking punch.

A draw ring 52 surrounds the die 48 and when the air cushion is inoperation draw ring 52 is held resiliently upwardly in a positionapproximately co-planar with the top of die 48 and with the blanking diering 51. To accomplish this result while still providing for freehorizontal movement of bolster 46 the following novel bolsterconstruction is provided. For convenience in fabrication bolster 46comprises a top plate 54 and a lower plate 55 which are screwedtogether. Lower plate 55 has a central opening which receives a pressureplate 56 which in its lowered position rests upon a ledge 57.

Pressure pins 58 are slidable in upper plate 54 of bolster 46 and restupon pressure plate 56. When pressure is applied within cylinder 43pressure pad 42 acts upwardly against plate 56 and pins 58 transmit thisupward movement to draw ring 52 to raise the same to working position.However, with the pressure off as shown in FIG. 4 there are no upward ordownward projections from bolster 46 so that the latter may be movedfreely to and from working position in a manner identical to thatpreviously described in connection with the embodiment of FIGS. 1through 3. The mechanism for actuating bolster 46 is identical with thecorresponding elements of FIGS. 2 and 3 and accordingly the samereference numerals have been applied thereto and the detaileddescription of this mechanism will not be repeated.

In the embodiment of FIG. 5 two die loading and unloading structures ofthe type shown in FIGS. 2 and 3 are provided so that two die sets fixedto and carried by two separate bolsters may be selectively andalternatively positioned on a press bed. This permits a quick change asbetween two die sets which are used successively and alternately andalso permits a die set to be unfastened and removed from one of thebolsters and another die set to be secured thereon while the otherbolster is in position on the press bed and a die s;t thereon is in useor in condition for use.

While the embodiment of FIG. 5 may be employed fore and aft, in thepresent instant the bolsters move onto the press bed from opposite sidesthereof. In FIG. 5 the press bed is designated 60 and opposite sidecolumns are designated 61 and 62. The guides which support oppositesides of the vertically reciprocable slide of the press are designated63 and 64. The two alternatively employable bolsters are designated 65and 66, the former being in working position on bed 60 and having a dieset 67 mounted thereon while a die set 68 mounted on idler bolster 66 isin position to be removed or on standby.

As in the preceding embodiments, the bolsters 65 and 66 have floorsupport carriages designated 69 and 70 which move on tracks 71 and 72 bymeans of motorpropelled wheels 73 and 74. At their proximal ends thebolsters 65 and 66 are supported by idler wheels 73 and 74 carried bybrackets 75 and 76. As shown in the case of bolster 65, as a bolsterreaches working position the wheels 73 thereof move onto a supportcarried by hydraulic lift means 81 the same as in the first embodiment,the latter then being lowered to deposit bolster 65 solidly on bed 60 asshown in FIG. 5. Here again locating pins 83 at the underside of bolster65 engage openings 84 in bed 60. Similar reference characters designatecorresponding elements for raising and lowering the other bolster 66when the latter is in working position on bed 60. In the illustratedinstance the supports 80 operate through openings in bed 60.

What is claimed is:

1. Apparatus for moving die sets to and from working position on a powerpress bed disposed above the adjacent floor, said apparatus comprising abolster for detachable securement to such press bed and adapted to havea die set secured thereon, support means at an edge of said bolsterextending downwardly toward said floor, wheel means at the lower end ofsaid support means to mount the same for rolling movement toward andaway from said press bed, and other wheel means at the opposite edge ofsaid bolster and projecting below the lower surface thereof for rollingmovement on said press bed as said bolster moves to and from its workingposition on said press bed, means at the edge of said press bed oppositeto said support means having surface portions substantially coplanarwith said press bed whereby said other wheel means roll thereonto as thebolster reaches its working position on the press bed, said wheel meanssupporting said bolster during rolling movement with the lower surfaceof the bolster inclined upwardly with respect to the press bed in adirection toward said other wheel means, and means for selectivelylowering said other wheel means to lower said bolster directly onto saidpress bed by pivotal movement thereof about the axis of said firstmentioned wheel means and raising said last mentioned means to disposesaid surface portions coplanar with said press bed for free rollingmovement of said other wheel means on said surface portions and saidpress bed.

2. Apparatus according to claim 1 wherein the lower surface of saidbolster is substantially tangent to an arc struck from the axis of saidfirst mentioned wheel means and of a radius equal to the verticaldistance from said axis to said press bed.

3. Apparatus according to claim 1 wherein said selective raising andlowering means comprises hydraulic pressure means.

4. Apparatus according to claim 2 wherein said selective raising andlowering means comprises hydraulic pressure means.

5. Apparatus according to claim 1 including power means for selectivelymoving said bolster and said support means toward and away from workingposition with respect to said press bed.

6. Apparatus according to claim 3 including power means for selectivelymoving said bolster and said support means toward and away from workingposition with respect to said press bed.

7. Apparatus according to claim 1 including electric motor means carriedby said support means for rotating said first mentioned wheel means formoving said support means and said bolster toward and away from workingposition with respect to said press bed.

8. Apparatus according to claim 3 including electric motor means carriedby said support means for rotating said first mentioned wheel means formoving said support means and said bolster toward and away from workingpositon with respect to said press bed.

9. A pair of die set moving apparatuses according to claim 1 disposed atopposite sides of a power press bed for alternative movement of eitherapparatus to working position with respect to said press bed withtheother apparatus in withdrawn position.

10. A die supporting bolster for use with power presses equipped withair cushions and adapted to transmit upward air cushion forces to diemechanism mounted thereon, said bolster comprising a body member havinga lower surface adapted to move upon a press bed to and from workingposition on said bed, a chamber in said body member and a verticallymovable horizontal platen member in said chamber, an opening in theunderside of said body member communicating with said chamber wherebyactivation of a power press die cushion causes the same to engageupwardly against said plate member and move the same resilientlyupwardly, a plurality of pressure pins mounted for vertical slidingmovement in said body member above said chamber and resting upon saidplate member, whereby vertical movement of the latter moves saidpressure pins upwardly to act against said die mechanism.

References Cited UNITED STATES PATENTS 2,625,896 1/1953 Immenroth 72-3283,134,350 5/1964 Danly 72416 3,183,828 5/1965 Clements 100299 3,207,0659/1965 Danly 100299 3,212,430 10/1965 Clements 10035 CHARLES W. LANHAM,Primary Examiner G. P. CROSBY, Assistant Examiner.

1. APPARATUS FOR MOVING DIE SETS TO AND FROM WORKING POSITION ON A POWERPRESS BED DISPOSED ABOVE THE ADJACENT FLOOR, SAID APPARATUS COMPRISING ABOLSTER FOR DETACHABLE SECUREMENT TO SUCH PRESS BED AND ADAPTED TO HAVEA DIE SET SECURED THEREON, SUPPORT MEANS AT AN EDGE OF SAID BOLSTEREXTENDING DOWNWARDLY TOWARD SAID FLOOR, WHEEL MEANS AT THE LOWER END OFSAID SUPPORT MEANS TO MOUNT THE SAME FOR ROLLING MOVEMENT TOWARD ANDAWAY FROM SAID PRESS BED, AND OTHER WHEEL MEANS AT THE OPPOSITE EDGE OFSAID BOLSTER AND PROJECTING BELOW THE LOWER SURFACE THEREOF FOR ROLLINGMOVEMENT ON SAID PRESS BED AS SAID BOLSTER MOVES TO AND FROM ITS WORKINGPOSITION ON SAID PRESS BED, MEANS AT THE EDGE OF SAID PRESS BED OPPOSITETO SAID SUPPORT MEANS HAVING SURFACE PORTIONS SUBSTANTIALLY COPLANARWITH SAID PRESS BED WHEREBY SAID OTHER WHEEL MEANS ROLL THEREONTO AS THEBOLSTER REACHES ITS WORKING POSITION ON THE PRESS BED, SAID WHEEL MEANSSUPPORTING SAID BOLSTER DURING ROLLING MOVEMENT WITH THE LOWER SURFACEOF THE BOLSTER INCLINED UPWARDLY WITH RESPECT TO THE PRESS BED IN ADIRECTION TOWARD SAID OTHER WHEEL MEANS, AND MEANS FOR SELECTIVELYLOWERING SAID OTHER WHEEL MEANS TO LOWER SAID BOLSTER DIRECTLY ONTO SAIDPRESS BED BY PIVOTAL MOVEMENT THEREOF ABOUT THE AXIS OF SAID FIRSTMENTIONED WHEEL MEANS AND RAISING SAID LAST MENTIONED MEANS TO DISPOSESAID SURFACE PORTIONS COPLANAR WITH SAID PRESS BED FOR FREE ROLLINGMOVEMENT OF SAID OTHER WHEEL MEANS ON SAID SURFACE PORTIONS AND SAIDPRESS BED.